1. Field of the Invention
The invention relates to improved rod bearings, and, more particularly, to an improved, sectional rod bearing for journaling a playing figure actuation rod in a fussball game table.
2. History of the Prior Art
This invention is directed to a bearing member for a fussball (also known as table soccer) game table generally of the type shown in U.S. Pat. No. 3,926,432. Typically, fussball game tables include a rectangular, box-like playing area supported on four legs. A plurality of axially slidable and rotatable rods are mounted on bearings and extend transversely of the playing area. The actuation rods each mount a plurality of playing figures which are arranged above the playing surface of the table in preselected formations. A light ball is placed on the playing surface and propelled by sharply rotating the actuating rods within their respective bearings, so that the foot of the playing figure strikes the ball and propels it along the playing surface toward one of the two goals located at opposite end walls of the table.
The rod bearings on prior art fussball tables are generally the most difficult portions of the table to service and maintain. In operation in a vending machine environment, the playing figure actuation rods gather dust from the environment and dirt and other soil from handling during operation. Because the actuation rods are continually being rapidly moved in an axial manner back and forth within the rod bearings dirt, debris and other matter deposited on the rods is scraped therefrom by the edges of the bearings. Consequently, the rod bearings must be removed and the bearing surfaces cleaned frequently to ensure smooth, rapid operation of the playing figure actuation rods.
Certain techniques for minimizing the maintenance required for fussball table rod bearings have been utilized in the past. For example, rod bearings have been constructed to include a circumferentially extending channel around the outside of the bearing so as to define a knife edge trough contiguous to the rod receiving aperture. This knife edge is intended to shave foreign material from the rod and collects it in the trough as the rod is slid back and forth within the bearing. This structure is intended to simplify maintenance by enabling one to merely clean the troughs periodically and avoid the time consuming removal of the bearings from the machine in order to effectuate cleaning. However, such bearing structures leave much to be desired in that a great deal of foreign matter is still collected on the interior bearing surface and may result in binding of the rods unless the bearings are periodically removed and the interior bearing surfaces thoroughly cleaned.
Prior art separable rod bearing structures overcome some of the maintenance difficulties such as ease of removal for cleaning. However, major problems are still present. For example, a rod moving in certain prior art bearings must be lubricated frequently in order to maintain as low friction as possible. In addition, the lubricant, typically a silicone spray material, builds up deposits on the rod which must be removed. The lubricant also attracts and holds dust and dirt to the rod further complicating rod bearing maintenance.
One solution to this prior art problem is set forth and shown in U.S. Pat. No. 4,382,598, invented by the applicant of the present invention. The structure of the separable rod bearing of that invention includes two semi-cylindrical pieces assembled with an anti-friction ring that virtually eliminates a need for lubricant. That design did not overcome all of the problems of prior art bearings, however. For example, one entire friction insert was made of teflon and although initially effective once this material becomes impregnated with debris from the rod it becomes just as abrasive as conventional material. In addition, material such as teflon have been deemed cost prohibitive in certain applications.
It would be an advantage to overcome the disadvantages of the prior art by providing a sectional rod bearing similar to that shown in U.S. Pat. No. 4,382,598 but without the need for an anti-friction ring and one that affords flexibility in adjustment and reliability in installation for maintaining the axial alignment of the aperture therethrough for receipt of the rod therein. Certain prior art structures such as that shown in the aforesaid U.S. Pat. No. 4,382,598 manifest a degree of warp upon the torquing of the various elements together through the fussball table wall. This axial misalignment occurs due to the pressures being applied to the outer flange of the sectional rod bearing that is not otherwise accommodated within the flange region. The unrelieved stresses produced during the torquing thereof may manifest themselves through the axial aperture to therein bind upon the rod. Any binding of the fussball rod reduces the efficiency of the game table and the actuation thereof.
It would be a distinct advantage to provide a sectional rod bearing structure which accommodates axial misalignment through means associated with the flange portion thereof for preventing binding of the rod therein. The present invention provides such a configuration by providing slotted sections in the flange region which slotted sections accommodate flexing of the flange upon the tightening thereof. Likewise, the anti-friction ring is eliminated and a material such as Delron is used for the fabrication of the entire rod bearing assembly.